The light is not lit when it is not positioned. After 3D positioning, it starts to blink(red).

The pins of the module are:

1.PPS, there is a second pulse output after positioning, the pulse period is 1s, and the high level lasts for 100ms, which is used for system synchronization.2. GND, ground.3.TX, RS-232 data output of the module.4. RX, RS-232 data input of the module.5.VCC, 3.6-5.5V, recommended 5.0V.6. BOOT, please hang out during normal work.